Saw this post in the Vindi Forums. Japan is getting an SAO themed event in which a costume from Kirito and a costume from Asuna will be available to players after a certain amount of certain boss monsters such as Lakoria, Gnoll Chieftain, and others are defeated. Also, a possible Yui Pet will be available. She is her Fairy self from the second half of the anime. Hopefully we'll be getting a similar event in the future considering how big a hit SAO was in the US.